CWE-291: Reliance on IP Address for Authentication

Description

The product uses an IP address for authentication.

IP addresses can be easily spoofed. Attackers can forge the source IP address of the packets they send, but response packets will return to the forged IP address. To see the response packets, the attacker has to sniff the traffic between the victim machine and the forged IP address. In order to accomplish the required sniffing, attackers typically attempt to locate themselves on the same subnet as the victim machine. Attackers may be able to circumvent this requirement by using source routing, but source routing is disabled across much of the Internet today. In summary, IP address verification can be a useful part of an authentication scheme, but it should not be the single factor required for authentication.

Potential Impact

Demonstrative Examples

sd = socket(AF_INET, SOCK_DGRAM, 0);serv.sin_family = AF_INET;serv.sin_addr.s_addr = htonl(INADDR_ANY);servr.sin_port = htons(1008);bind(sd, (struct sockaddr *) & serv, sizeof(serv));
                     while (1) {memset(msg, 0x0, MAX_MSG);clilen = sizeof(cli);if (inet_ntoa(cli.sin_addr)==getTrustedAddress()) {n = recvfrom(sd, msg, MAX_MSG, 0, (struct sockaddr *) & cli, &clilen);}}

while(true) {
                        DatagramPacket rp=new DatagramPacket(rData,rData.length);outSock.receive(rp);String in = new String(p.getData(),0, rp.getLength());InetAddress clientIPAddress = rp.getAddress();int port = rp.getPort();
                           if (isTrustedAddress(clientIPAddress) & secretKey.equals(in)) {out = secret.getBytes();DatagramPacket sp =new DatagramPacket(out,out.length, IPAddress, port); outSock.send(sp);}
                     }

Mitigations & Prevention

Real-World CVE Examples

Related Weaknesses

Taxonomy Mappings

• CLASP: — Trusting self-reported IP address